A dichotomous key is provided for determining the different species of butterflies of the genus Morpho from Colombia, with ilustrations of the male genitalia and dorsal and ventral pictures of representative males and females of the main subgenera. For the study of the taxonomic characteristics of the species, the parameters given by Clarke (1941) were followed with some modifications that simplified the use of this technique. Wing morphometrics and coloration patterns and mal e genitalia features were also included, in some cases, references of the literature were given (Le Moult & Real, 1962; Blandin, 1984).